import React, {Component} from 'react';
import './index.css';

export default class Footer extends Component {
    //全选的回调
    handleCheckAll=(event)=>{
        this.props.checkAllTodo(event.target.checked)
    }
//清楚所有已完成的回调
    handleClearAll=()=>{
        this.props.clearAllDone()
    }

    render(){
        const {todos} = this.props
        //已完成
        const doneCount = todos.reduce((pre,todo)=>{
            return pre + (todo.done?1:0)
        },0)
        //总数
        const total = todos.length

        return (
            <div className="todo-footer">
                <label>
                    <input type="checkbox" onChange={this.handleCheckAll} checked={doneCount==total&&total!=0?true:false}/>
                </label>
                <span>
                    <span>已完成{doneCount}/span>/全部{total}</span>
                </span>
                <button className="btn btn-danger" onClick={this.handleClearAll}>清除已完成任务</button>
            </div>
        )
    }
}